1. Field of the Invention
The present invention relates generally to thermal expansion in marine transmissions and more specifically to a bearing arrangement to reduce the effects of thermal expansion in a marine transmission, which locates thrust bearings for a clutch shaft assembly as close as possible to reduce the effects of thermal expansion.
2. Discussion of the Prior Art
It is a common practice to fabricate marine transmission housings out of aluminum castings to reduce the overall weight of a transmission. However, aluminum castings have a different thermal expansion coefficient than steel; elements of clutch shaft assemblies are fabricated from steel. The greater the distance between thrust bearings retaining the clutch shaft assembly, the greater the disparity of thermal expansion lengths between the housing and the clutch shaft. The effect of the disparity between thermal expansion lengths is damage to the marine transmission housing, gears, bearings and other internal components at temperature extremes. It appears that the prior art fails to provide a solution to the problem of thermal expansion in marine transmissions.
Accordingly, there is a clearly felt need in the art for a bearing arrangement to reduce the effects of thermal expansion in marine transmission, which locates thrust bearings for a clutch shaft assembly as close as possible to reduce the effects of thermal expansion between dissimilar materials through the use of a special wear resistant thrust washer.